Mirror finish using angle grinder?

Thanks so much for your detailed response Obsessed. If you advocate using green compound manually how do you propose I go about a mirror polish on my khukuri? Consider me a newbie when you respond. Thanks for your time.
 
Amko said:
Thanks so much for your detailed response Obsessed. If you advocate using green compound manually how do you propose I go about a mirror polish on my khukuri? Consider me a newbie when you respond. Thanks for your time.
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I'd still suggest using an AlOx compound for that job. Popular polishes like Simichrome or Flitz or Mother's Mag work well. It'll work much faster, especially if doing it by hand.

BUT, if you still want to use the green compound, a wooden block with some denim wrapped around it, and loaded up with the green compound, could work relatively well. Denim is able to hold a lot more compound, in a much denser layer. That'll help it work more efficiently (faster), when polishing by hand. The AlOx compounds will also work very, very well, used in the same manner.

Depending on how rough the blade finish is now, you might also think about doing some sanding of the blade first, before going straight to the polishing compound. Starting at something like 320 or 400-grit, then progressing through a sequence like 600 > 800 > 1000 > 1500 > 2000 will put the finish at very near-mirror, after which the polishing pastes will make it really pop.
 
Excellent, thanks. Just checked my blade. It is close to mirror. Which is why I was thinking about the angle grinder. I'm using Autosol as I speak and will apply/buff, probably multiple times. Will keep you posted!

Edit: Still not "popping"...I last sanded at 3000. Do I go back a few grades say 2000-2500 and re-sand? Then use the Autosol again?
 
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Amko said:
Excellent, thanks. Just checked my blade. It is close to mirror. Which is why I was thinking about the angle grinder. I'm using Autosol as I speak and will apply/buff, probably multiple times. Will keep you posted!

Edit: Still not "popping"...I last sanded at 3000. Do I go back a few grades say 2000-2500 and re-sand? Then use the Autosol again?
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By 'not popping', if you're still noticing scratches in the finish, odds are you'll need to go back a few grit levels to clean up the scratches you're seeing. Maybe go back to ~ 800 - 1000 or so, then follow again with 2K & 3K, being very meticulous in making sure all coarser scratches are getting cleaned up, before moving finer in grit. At 2K or so, it should be very near-mirror under bright light & close examination, if all the prior work was good.

If still using a powered buffer of some kind, make sure the buffing wheel is clean when you start. Just a little bit of dirt or other grit in the buff will leave a lot of fine scratches, no matter what else you're doing.
 
I went back to 1200…1500...2000...2500...3000. Shiny but not mirror. I'm waiting on green compound, can I charge it with a leather strop block and then rub it across the blade? Is this ok? Then try the metal polish I have, Autosol? Thanks.
 
Amko said:
I went back to 1200…1500...2000...2500...3000. Shiny but not mirror. I'm waiting on green compound, can I charge it with a leather strop block and then rub it across the blade? Is this ok? Then try the metal polish I have, Autosol? Thanks.
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Buy a tube of Flitz metal polish and you'll be amazed!
 
Amko said:
I went back to 1200…1500...2000...2500...3000. Shiny but not mirror. I'm waiting on green compound, can I charge it with a leather strop block and then rub it across the blade? Is this ok? Then try the metal polish I have, Autosol? Thanks.
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If still not approaching a mirror, I'd suspect there are some scratches left from a grit stage before the 1200 at least, and maybe further back if the 1200 and following sequence still aren't cleaning them up. It's a common issue with trying to mirror-polish a blade; really have to be diligent about making sure each grit stage does all it can do, before moving on to following grit stages.

Regarding the green compound, use it if you want to. But chances are, any aluminum oxide polish (such as your Autosol) will do anything the green will, and more effectively. As with the sanding sequence, the polish will work better and much easier if the prior finishing stages are taken as far as they can be taken.

As suggested in the previous post, some pics of the blade as you go would clarify what needs to be done to solve remaining issues.
 
Amko said:
http://i346.photobucket.com/albums/p407/amko1967/Mobile Uploads/IMG_20181128_181111_zpsez1fh1il.jpg

Thanks, Obsessed. Here's a photo of my Himalayan Imports British Army Service khukuri.
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That looks pretty darn good by the picture, better than what I'd assumed based on your descriptions so far. If it were mine, I'd likely be pretty happy with that.

That being said, if you're still inclined to do any more with it, take it in small, careful steps. It may be, with the few issues remaining that are keeping it short of full-mirror, you might be able to gradually work it out with fine-grit or very-fine-grit sanding (let's say ~ 800-grit or higher) and/or polishing/buffing over time. You might be at a point, finish-wise, where trying to go too far back in grit might create more troubles than are solved in doing so.
 
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Amko said:
http://i346.photobucket.com/albums/p407/amko1967/Mobile Uploads/IMG_20181101_232600_zpsuoxiskcf.jpg

Here's a photo of the knife before I used it. You can see the mirror finish. I was hoping to restore it to that level.
Assuming I were to use a powered buffing wheel, which compound do you think you would recommend? Based on your feedback I cancelled the order for green compound. Thanks.
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The stick or crayon-type compounds made for powered buffing wheels should work well. They're bound with a waxy substance (stearin or similar) to make it hold onto the cotton buff, without being thrown off. Something like white rouge, or others labelled specifically for polishing 'hard metals' or 'stainless steel'. They'll typically be aluminum oxide. Look for white first, then maybe grey (a little coarser than white, but still works well). Avoid the black compounds or others labelled for 'cleaning' hard metals or stainless, as they're usually much coarser for cleaning heavily scaled or roughly-finished pieces, and probably overkill for this job.
 
Thanks again. Is it ok if I ask you for a link to a compound, on Amazon.com? If not, at least a brand name/type. Time is of the essence. I'm in India. I need to order asap, a friend traveling in the US will carry it back to India next week. Said compound/s you recommended above aren't locally available.
Edit: Just checked my local Amazon, saw a crayon-type white polishing compound and here's the description:
"Luxor White has 0.3 micron grit and is used for preparation of platinum, white gold, silver, and stainless steel, or for polishing gold parts with diamonds."
Think this will do?
 
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Amko said:
Thanks again. Is it ok if I ask you for a link to a compound, on Amazon.com? If not, at least a brand name/type. Time is of the essence. I'm in India. I need to order asap, a friend traveling in the US will carry it back to India next week. Said compound/s you recommended above aren't locally available.
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In the states, compound's like Ryobi's White Rouge can be found at Home Depot; it's usually sold in a set of about 3 compounds also including a 'yellow' compound that is intended also for stainless steels. I've also used a grey compound from Sears (Craftsman brand) that works very similarly, and they also carry a white compound that should work well. The grey compound is seen in the set below, labelled as number '2'. Their white compound is labelled as number '5', but not seen in the set pictured here:

spin_prod_947435312


If your friend searches the big-box hardware outlets like Home Depot or Lowe's, or Sears (going out of business soon, probably), looking for any of these compounds labelled for polishing hard metals and/or stainless steel is an easy way to find them. Don't worry too much about brands, as they're all pretty common and most any of them should work well enough.
 
Just placed an order for a locally available white polishing compound that claims to deliver a mirror finish on steel, silver, gold etc. Also another for a Makita angle grinder (as I said before, have a couple of projects in mind, nothing to do with knives) and a couple of felt buffing wheels. Will update.
 
Obsessed, question: once the white compound is here, how do I 'charge' the wheel with it? I've seen folks on YouTube fix compound on a vice and then run the wheel over it. Is that what I need to do? Does the compound need to be moistened with water? Thanks.
 
The compound is grease-based and is essentially a giant crayon with abrasive in it. The heat of the friction from the wheel melts the compound and it loads the wheel.
 
Thanks FortyTwoBlades. I'm excited to be doing this for the first time as you can imagine from my questions!
 
Amko said:
Obsessed, question: once the white compound is here, how do I 'charge' the wheel with it? I've seen folks on YouTube fix compound on a vice and then run the wheel over it. Is that what I need to do? Does the compound need to be moistened with water? Thanks.
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FortyTwoBlades covered it exactly. :thumbsup:
 
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